Disk Replacement - NAS 540

MickBB

I want to copy back data form new 8TB into old 3TB. So I need to have access to this partition on new 8TB disk. 

Mijzelf

Something went wrong. The starts of sda3 and sdb3 should be the same. The ends of sda2 and sdb2 are, but for some reason a partition editor have moved the start of sda3 for 262144 sectors, which is 128MiB. So assuming that partition editor left the content of sda3 intact, the internal data structures cannot be found because they are on the wrong place.

The partition manager also changed the partition type to 'Microsoft basic data', but I don't think that matters, Linux ignores that, AFAIK.

So use a decent partition editor, like fdisk on the NAS, to remove sda3 and create it again. It should put the start on 7999488 (sectors), and the size at least 5852532736. fdisk will default to that start, but for size it will suggest to use the whole remaining disk. Which should be fine.

MickBB

As I understand it, I have to use fdisk when logging in through the ssh server? Can I pull the drive out of the NAS and use Paron Hard Disk Manager?

Mijzelf

As I understand it, I have to use fdisk when logging in through the ssh server?

Confirm.

Can I pull the drive out of the NAS and use Paron Hard Disk Manager?

In theory, yes. If it allows you to create a partition starting exactly at sector 7999488, and if it does not helpfully do something with the contents of the created partition.

MickBB

I try to do it using Pargon. I try to extend partition. During that the Pargon crashed. I put back the disk to the NAS. I checked the disk in NAS as you wrote before. The output data is the same as I sent before. Is there a possibility that you could help me and give me the command witch I have to use to resolve that problem. It will be a great help. Thanks a lot for your assistance. 

MickBB

Mijzelf

Right. Pargon is too helpful. That 128MB 'unallocated' before disk X is the raid header. Disk X itself is the payload of the raid array, which is indeed an ext4 filesystem. So Pargon looked at the partitions, didn't recognize the raid header, found the ext4 filesystem and decided to move the start of the partition.

Which means that sda3 should be mountable, as it is a valid filesystem. If your only goal at the moment is to copy your data, you could try to mount it:

mkdir /i-data/sysvol/admin/rescue

su

mount /dev/sda3 /i-data/sysvol/admin/rescue

When that doesn't give errors, your data should be accessible in your admin share, in subdirectory rescue.

MickBB

Thank you for help. Disk is OK.